Revisit Elk, Sprotty cardinality

[nrbgt]

We might only need One Elk and One Sprotty Server, as it appears they can both handle multiplexing requests.

It would still be good to be able to cull them when there are no more views on the page, probably.

[dfreeman06]

Example attempt below:

+const Theelk = new ELK.default({
+  workerFactory: () => {
+    ELK_DEBUG && console.warn('ELK Worker created');
+    return new (Worker as any)();
+  }
+} as any);
+
 export class ELKModel extends DOMWidgetModel {
   static model_name = 'ELKModel';
 
@@ -91,24 +98,25 @@ export class ELKModel extends DOMWidgetModel {
   }
 
   protected cullElk() {
-    const elk: any = this._elk;
-    if (elk != null) {
-      ELK_DEBUG && console.warn('ELK worker culling for', this.cid);
-      elk.worker?.terminate();
-    } else {
-      ELK_DEBUG && console.warn('ELK was already culled for', this.cid);
-    }
-    this._elk = null;
+    // const elk: any = this._elk;
+    // if (elk != null) {
+    //   ELK_DEBUG && console.warn('ELK worker culling for', this.cid);
+    //   elk.worker?.terminate();
+    // } else {
+    //   ELK_DEBUG && console.warn('ELK was already culled for', this.cid);
+    // }
+    // this._elk = null;
   }
 
   protected ensureElk() {
     if (this._elk == null) {
-      this._elk = new ELK.default({
-        workerFactory: () => {
-          ELK_DEBUG && console.warn('ELK Worker created');
-          return new (Worker as any)();
-        }
-      } as any);
+      this._elk = Theelk;
+      // this._elk = new ELK.default({
+      //   workerFactory: () => {
+      //     ELK_DEBUG && console.warn('ELK Worker created');
+      //     return new (Worker as any)();
+      //   }

[dfreeman06]

Added A TheElk 3e118f6